Submitted to: Communications in Soil Science and Plant Analysis
Publication Type: Peer reviewed journal
Publication Acceptance Date: 7/11/2001
Publication Date: 10/3/2001
Citation: Sistani, K.R., Rowe, D.E., Miles, D.M., May, J.D. 2001. Effects of drying method and rearing temperature on broiler manure nutrient content. Communications in Soil Science and Plant Analysis. 32:2307-2316. Interpretive Summary: Poultry litter provides more incentive for utilization as a source of plant nutrient than other animal manures because it contains greater concentration of nutrients such as nitrogen and phosphorus. It is imperative that field crop and pasture producers to closely monitor the nutrient input credited to manure application. An accurate chemical analysis of manure/litter is the key to the determination of precise rates of manure application. This study was conducted to determine the effect of pre-analysis drying methods and the bird-rearing temperature on broiler manure nutrient content. The results indicated that all drying methods caused reduction in nitrogen as high as 27% compared to fresh manure analysis. However, statistically, no significant differences were observed among the drying methods tested in this experiment. The effect of drying methods followed the same trend for all three rearing temperatures. The greatest loss of metal nutrients and phosphorus were observed with freeze-drying method.
Technical Abstract: Proper sample preparation and optimization of the techniques for manure chemical analyses are the keys to the determination of precise rates for land application to crops and pastures. This study was conducted to determine the effect of bird-rearing temperature (RT) and pre-analysis drying methods on broiler manure nutrient content. Four drying methods, air drying (AD), freeze drying (FD), oven drying at 65 C (OD65), and oven drying at 105 C (OD105) were evaluated on manure of birds grown at 16, 21, and 26oC. The results were compared with analysis of the fresh broiler manure with no drying (ND). All drying treatments resulted in highly significant N loss (21%-27%) compared to ND at all rearing temperatures. However, there were no significant differences in total N loss among the four drying methods examined in this experiment. There was significant loss of NH4-N with OD105 for all RT, but no pattern was observed among other drying methods and RT with regard to NH4-N and organic N. The effect of drying methods on broiler manure nutrient content followed the same trend for all the rearing temperatures. The greatest loss of P, Ca, Mg, K, Fe, Mn, and Zn were observed with freeze drying. We recommend fresh broiler manure analysis for the determination of total N and NH4-N after a proper mixing to obtain a homogeneous paste. For analyses of P, Ca, Mg, K, Fe, Mn, and Zn in the broiler manure, ND, AD, and OD65 generally resulted in lower reduction of these nutrients.